Ocular inflammation generally relates to inflammation of any part of the eye, including both intraocular inflammation and inflammation of the sclera. Intraocular inflammation can be further divided into inflammation of the anterior segment (located between the iris and the cornea) and inflammation of the posterior segment (vitreous cavity). Each type of ocular inflammation can exhibit a different form of inflammation that can be measured in different ways.
Clinicians can diagnose ocular inflammation based on a clinical exam that employs a diagnostic device, such as a slit lamp microscope or an indirect ophthalmoscope. Based on the clinical examination, the clinician can grade the extent of the ocular examination based on a standard, categorical scale. The standard, categorical scale is designed to allow for comparison in both clinical practice and clinical trials; however, the rankings suffer from variability between clinicians and even between patients with the same clinician. Moreover, although each type of ocular inflammation can exhibit different forms of inflammation, the extents of the different types of ocular inflammation can be graded according to the same standardized, categorical scale with a finite number of grades, such as the six-grade scale (providing rankings of 0, trace, 1+, 2+, 3+ and 4+) provided by the Standardization of Uveitis Nomenclature (SUN) Working Group. However, since the scale includes a finite number of grades, there is an inability to discern small changes in inflammation grades, which could be clinically significant.